Haloalkyl-4-thiazolidinone

ABSTRACT

Compounds of the formula   AND   WHEREIN R and R1 are -CF2H, CF2Cl, -CF3 or -C2F5, R2 is hydrogen, alkyl, alkenyl, aryl, aralkyl, hydroxyalkyl, carboxyalkyl, or haloalkyl of up to 8 carbon atoms; X is polymethylene of up to 8 carbon atoms, or -CH2CO-CH2-. R3 and R4 are hydrogen, aryl, alkaryl, aralkyl, cycloalkyl, alkyl or carboxyalkyl each of up to 8 carbons, and n is 0, 1 or 2 can be made by reaction of an Alpha -mercapto acid with a haloalkylidene imine (Schiff base). If desired the heterocyclic sulfur atom can be oxidized and/or substituents introduced into nitrogen by conventional methods. The compounds are useful as plasticizers and in some instances as plant hormones.

Elite Raasch States Patent [191 l 5 HALOALKYL-4-THIAZOLIDINONE [75} Inventor: Maynard S. Raasch, Wilmington,

Del.

[73] Assignee: E. l. du Pont de Nemours and Company, Wilmington, Del.

[22] Filed: Dec. 30, 1971 [21] Appl. No.: 214,378

OTHER PUBLICATIONS Zeifman et al., Chem. Abstracts, 61:16065-16066 and 62:540-541 (1964).

Primary ExaminerRichard J. Gallagher [57] ABSTRACT Compounds of the formula [4 1 Dec. 10, 1974 and wherein R and R are CF H, CF CI, CF or C F R is hydrogen, alkyl, alkenyl, aryl, aralkyl, hydroxyalkyl, carboxyalkyl, or haloalkyl of up to 8 carbon atoms;

X is polymethylene of up to 8 carbon atoms, or Cl-l COCl-l R and R are hydrogen, aryl, alkaryl, aralkyl, cycloalkyl, alkyl or carboxyalkyl each of up to 8 carbons, and n is 0, l or 2 can be made by reaction of an a-mcrcapto acid with a haloalkylidene imine (Schiff base). If desired the heterocyclic sulfur atom can be oxidized and/0r substituents introduced into nitrogen by conventional methods. The compounds are useful as plasticizers and in some instances as plant hormones.

8 Claims, N0 Drawings 1 HALOALKYL-4-THIAZOLIDINONE FIELD OF INVENTION This invention relates to novel 4-thiazolidinones, having at least two fluorines oneach 1-2 carbon hydrocarbyl or halohydrocarbyl group in the 2-position.

BACKGROUND OF THE INVENTION Numerous 4-thiazolidinones have been prepared and used in biological applications. For example, Bishop et al. J. Chem. Soc. 2384-5 (1963) describes the compounds H s ocia l NH and

o (W (CF92 and ibid p. 1531 have reported No 4-thiazolidinones have been reported with fluoroalkyl groups bonded directly to the 2-position.

DESCRIPTION OF THE INVENTION The compounds of the present invention are heterocyclic compounds having the formula wherein n is 0, l or 2 R and R are each selected from CH I-l, CF Cl, CF or C F R and R are hydrogen, aryl, aralkyl, alkaryl, alkenyl, cycloalkyl, alkyl or carboxyalkyl each of up to 8 carbon atoms.

R is hydrogen, alkyl, alkenyl, aryl, aralkyl, hydroxyalkyl, carbalkoxy, and haloalkyl each of up to 8 carbon atoms, and

X is polymethylene of up to 8 carbon atoms, or CI-I COCH In the above the term hydrocarbyl isemployed t designate a radical derived from a hydrocarbon by removal of a hydrogen atom. The term includes aryl groups derived from hydrocarbons having a benzene ring by removal of a nuclear hydrogen atom, alkaryl groups wherein the hydrocarbyl group is formed by removal of an aliphatic hydrogen atom from a benzene compound having at least one lower alkyl side chain, cycloaliphatic groups derived from a hydrocarbon having a ring of three or more carbon atoms by removal of an aliphatic hydrogen atom, and alkyl groups derived from alkanes by removal of an aliphatic hydrogen atom.

The term lower alltyl is intended to mean alkyl groups of up to four carbon atoms unless otherwise 'limited.

The term lower acyl isintended to'mean acyl groups derived from alkanoic acids having up to four carbon atoms.

The compounds are made by reacting a-mercapto acids or esters with fluoroalkylidenimines. Procedures for preparing the imines are described by W. J. Middleton and C; G. Krespan, J. Org. Chem, 30, 1398 (1965), W. J. Middleton, US. Pat. No. 3,342,864 (1967), and Y. V. Zeifman et al., Proc. Acad. Sci. USSR, 153, 1032 (1963). The reaction may be carried out in the absence of solvent. In the case of rapid reactions, an inert solvent may be useful to moderate the reaction. Such solvents include carbon disulfide, dichloromethane, chloroform, carbon tetrachloride, 1,2- dichloroethane, 1,1,1-trich1oroethane, 1 ,2,2-trichloro- 1,1,2-trifluoroethane, benzene, chlorobenzene, toluene, hexane, ether, 1,2-dimethoxyethane and acetonitrile. Depending on the reactivity of the reactants and the physical properties of the imine, the reaction is carried out with cooling, heating in an open vessel or under reflux, or by heating in a sealed vessel. The products are isolated and purified by conventional methods, such as crystallization and distillation.

When the reaction is carried out with an imine of the formula RR@NI-I, the resulting heterocycle contains an NH group upon which substitution reactions may be performed. N-derivatives of heterocycles are conveniently made by forming an alkali metal salt (e.g., lithium, sodium, or potassium) and treating with a halogen compound as illustrated by Examples 1 l-17. This may be done in the absence of a solvent, but the use of polar solvents such as alcohols, dimethylformamide, dimethyl sulfoxide, and hexamethylphosphoramide is advantageous.

The heterocyclic sulfur atom in the above compounds can be oxidized by peracetic acid to give either the l-oxide or the 1,1-dioxide as shown in' Example 9.

These new compounds are all useful as plasticizers for such polymers as polyvinyl chloride. They are incorporated preferably in solution in the polymer at amounts of 5-50 percent by weight. The exact amount depends upon the degree of plasticization required but r 2 ,2-Bis( trifluoromethyl )-3 -pheny1-4-thiazo1idinone generally -30 percent give desired properties in the polymeric material.

Some of the compounds of the present invention, notably 2,2-bis(chlorodifluoromethyl)-4-thiazolidone, have plant hormone activity. Its N-methy1 derivative 5 stimulates the production of ethylene by plants.

This invention is further illustrated by the following examples which should not, however, be construed as fully delineating the scope of this discovery.

EXAMPLE 1 2,2-Bis( trifluoromethyl )-4-thiazolidinone I 7(0 F3): 0 N

Anal. Calcd. for C5H3F6NOS: C, 25.10; H 1.26; N, 5.86

Found: C, 25.13; H. 1.16; N, 5.64.

. 7 EXAMPLE 2 2,2-Bis(trifluoromethyl)-3-methyl-4-thiazolidinone /S (on):

N-Methylhexafluoroisopropylidenimine (7.16 g, 0.03

mol), 3 ml of dichloromethane and 3.03 g (0.033 mol) of mercaptoacetic acid were sealed in a glass tube and heated at 100C for 16 hours. The product was washed with water; yield, ca 7 g (91 percent). After recrystallization from hexane it melted at 4749C. 50

Anal. Calcd. for C H F NOS: C, 28.47;

H, 1.99 Found: C, 28.77; H,

EXAMPLE 3 S on):

A mixture of 9.64 g (0.04 mol) of N*(hexafluoroisopropylidene)ani1ine'and 3.88 g (0.044 mol) of mercap- Q toacetic acid was heated on a steam bath for 4 hours.

The viscous syrup crystallized when stirred with 25 ml of 5 percent sodium hydroxide solution. The product was filtered off and washed with water. It was recrystallized from methanol by cooling in Dry Ice; yield. 4.02 g (32 percent) in 3 crops. This was sublimed to give 3.47 g, mp 109.5110.5C; H nmr (CDCI 3.78 ppm (s, CH 7.4 (m, C H F nmr 70.5 ppm (s, vs F-] 1).

Anal. Calcd. for C H F NOS: C, 41.90; H. 2.24; N. 4.44;

5.10.17 Found: C. 41.63; H. 2.17; N. 4.52;

EXAMPLE 4 2,2-Bis(trifluoromethyl )-5 -methyl-4-thiazolidone ens T0 F3):

The reaction was carried out as in Example 1 except that 5.83 g of thiolactic acid was used in place of mercaptoacetic acid. The product (7.94 g) was recrystallized from hexane to give 7.14 g (57 percent), mp 86.588.5C, H nmr (CDCl 2.57 ppm (d, CH 4.07 (quartet, CH), 8.92 (broad peak, NH); ir 3.14,

3.23 p. (NH), 3.47 (sat. CH), 5.82 (lactam C=O).

Anal. Calcd. for C H F NOS: C, 28.47; H. 1.99; N, 5.53

Found: C. 2863; H, 1.88; N, 5.58.

EXAMPLE 5 2,2-Bis(tri-fluoromethyl )-5 ,5-dimethyl-4-thiazolidinone Z-Mercaptoisobutyric acid (2.87 g, 0.024 mol) and 4.8 g (0.029 mol) of hexafluoroisopropylidenimine were sealed in a glass tube and heated at C for 20 hours. The product was washed with 5% sodium bicarbonate and water. Recrystallization from hexane gave 2.35 g (37 percent), mp 128129C.

Anal. Calcd. for C H F NOS: C, 31.47; H,

2.64; N, 5.24 Found: C, 31.26; H. 2

EXAMPLE 6 5-Carboxymethyl-2-,2-bis(trifluoromethy1)-1,3- thiazolidin-4-one Hexafluoroisopropylidenimine (8.25 g, 0.05 mol), ml of ether, and 7.50 g (0.05 mol) of mercaptosuccinic acid were sealed in a glass tube and heated at 100C for 20 hours. The ether was evaporated and the product was washed with water and air dried; yield, 10.4 g (66 percent). Recrystallization from nitromethane left 9.1 g, mp 203208C; H nmr [(CD CO] ABX pattern 1.40 ppm (quartet, 2 upfield components split into doublets, J 11 Hz; 2 downfield components split to doublets, J 4 Hz; CH 2.75 (pair of doublets, J 4, CH) 7.10 (s, OH NH, removed by D 0); F nmr 9.2 ppm (A B pattern, vs CCI FCCI F); ir 3.15; 3.25 u(NH), 3.46 (sat. CH), 3-4 ,1. (background absorption, COOH), 5.81, 5.85 (C=O).

Anal. Calcd. for C,H F NO;,S: C, 28.28; H, 1.70; N, 4.71 Found: C, 28.41; H. 1.57; N. 4.95.

' EXAMPLE 7 2-(Chlorodifluoromethyl)-2-(trifluoromethyl)-4- thiazolidinone Chloropentafluoroisopropylidenimine (4 g, 0.022 mol) was added to 2.21 g (0.024 mol) of mercaptoacetic acid in 3 ml of dichloromethane with occasional cooling. After 16 hours the solvent was boiled off and the product was washed with water and air dried. Recrystallization from hexane left 3.80 g (68 percent) mp Anal. Calcd. for C H ClF NOS: C, 23.50; H, 1.18;

1,3-Dichlorotetrafluoroisopropylidenimine (6.55 g, 0.033 mol) was added slowly to 3.34 g (0.036 mol) of mercaptoacetic acid in 3 ml of dichloromethane and the solution was allowed to stand 1 hour. The solvent was boiled off and the product was washed with water. After air drying, the compound (5.88 g) was-recrystallized from hexane; yield, 5.60 g (62 percent); mp l03.5-104.5C; H nmr (CDCl 3.75 ppm (s, CH 9.09 (broad peak, NH); F nmr 59 ppm (A 8 pattern).

Anal. Calcd. for C H Cl F.,NOS: C. 22.08; H, 1.11; N, 5.15

Found: C. 2206;1-1, 1.09; N, 4.85.

EXAMPLE 9 2,2-Bis(chlorodifluoromethyl)-4-thiazolidinone 1,1- dioxide Anal. Calcd. for C H Cl F NO S: C, 19.75;

H, 0.99; N, 4.61 Found: C, 20.02; H, 0

By using a thiazolidinone:peracetic acid ratio of 1:1, the sulfoxide is obtained.

EXAMPLE l0 2 ,2-Bis( chlorodifluoromethyl )-3-methyl-4- thiazolidinone s I W( C I 2 C1) 2 0 NCI-Iz 2,2-Bis(chlorodifluoromethyl )-4-thiazolidinone (4.1 g, 0.015 mol) was dissolved in 5 ml of water containing 0.6 g (0.015 mol) of sodium hydroxide. After addition of 10 ml of methanol and 2.56 g (0.018 mol) of methyl iodide, the solution was allowed to stand for 18 hours. The product was precipitated with water and filtered off (3 g). REcrystallization from hexane gave 2.66 g (62%) in two crops, mp 84-85C.

Anal. Calcd. For C H Cl- F NOS: C, 25.18; H, 1.76; N, 4.90

Found:

C, 24.86; H, 1.55; N, 4.71

EXAMPLE 1 l 2,2-Bis(chlorodifluoromethyl)-3-ethyl-4- thiazolidinone I s j women; 0 N zHs 2,2-Bis(chlorodifluoromethyl)-4-thiazo1idinone (8.16 g, 0.03 mol) was dissolved in 10 ml of H and 20 ml of ethanol Containing 1.2 g (0.03 mol) of sodium hydroxide. Ethyl iodide (6.2 g, 0.04 mol) was added and the mixture was refluxed for hours. The ethanol was evaporated and the product was taken up in ether and washed three times with 5 percent potassium hydroxide. The ether solution was dried (MgSO and distilled to give the ,ethyl derivative, bp 586lC' (0.2 mm). Crystallization from pentane by cooling in Dry Ice gave 1.8 g (20 percent) of a camphorlike solid, mp 45 47,C.

Anal. Calcd for C H Cl F,NOS:

Found:

EXAMPLE 1 2 2,2-Bis(chlorodifluoromethyl )-3-butyl-4- thiazolidinone The butyl derivative was made analogously to the ethyl derivative (Example 1 l) but using n-butyl iodide instead of ethyl iodide; bp 7l72C (0.15 mm).

Anal. Calcd for C H CI F NOS: C, 32.93;

H, 3.38; Found: C, 33.04; H, 3

4 EXAMPLE 1 3 3-Allyl-2,2-bis( chlorodifluoromethyl)-4-thiazolidinone S I T rrain O NCHQ CH=CH Anal. Calcd for C H,CI,F,NOS: C. 30.79; H, 26;

2. N. Found: C. 30.91; H, 2.38;

The reaction wasalso run in dimethylsulfoxide.

EXAMPLE l4 3-Benzyl-2,2-bis(ch1orodifluorornethyl )4- thiazolidinone bp 103-105C (0.5 mm) and recrystallized from methanol to give 3.0 g (27 percent) mp 43-44C.

Anal. Calcd for C H Cl ENOS: C, 39.79; H. 2.51:

Found: C. 39.31: H. 2.33;

EXAMPLE 15 2,2-Bis( chlorodifluoromethyl )-3-( Z-hydroxyethyl )-4- thiazolidinone s l oncm 0- Ncmomon The hydroxyethylation was carried out as described for the allyl derivative (Example 13) but using 2- iodoethanol'instead of allyl chloride. The compound was distilled at 98l00C (0.1 mm); 56 percent yield.

Anal. Calcd for C H Cl F NO S: C, 26.60; H. 2.23; Found: C, 26.20; H, 2

' EXAMPLE l6 2,2-l3is(chlorodifluoromethyl )-3-carbethoxymethyl-4- thiazolidinone s omom The carbethoxymethyl derivative was made analogously to the ethyl derivative (Example 1 l except that ethyl bromoacetate was used in place of ethyl iodide.

The product distilled at 93C (0.1 mm); 66 percent yield.

Anal. Calcd for C H CI RNO S: C, 30.18; H, 2.53; Found: C, 29.80; H, 2.65;

The reaction was also carried out in dimethylsulfoxide instead of ethanol-water.

The ester can be hydrolyzed to the acid.

EXAMPLE l7 1 ,4-Bis[ 2,2-bis( chlorodifluoromethyl )-4-thiazolidinon- 3-yl lbutane To a solution of 8.16 g (0.03 mol) of 2,2- bis(chlorodif1uoromethy1)-4-thiazolidinone in m1 of ethanol was added 2 g (0.03 mol) of potassium hydroxide in 15 ml of ethanol followed by 4.7 g (0.015 mol) of 1,4-diiodobutane. The mixture was refluxed for 16 hours on a steam bath and the ethanol was then boiled off. The product was washed with water and recrystallized from methanol to give 3.25 g (36 percent) mp 134-136C.

To 4.05 g (0.044 mol) of mercaptoacetic acid in 8 ml of dichloromethane was added 5.88 g (0.04 mol) of pentafluoroisopropylidenimine [W. J. Middleton, U.S. Pat. No. 3,342,864 (1967)]. After the solution had stood for 16 hours the solvent was boiled off and the Anal. (ulcd for C H ChF N O S- C, 28.11; H, 2.02; N, 4.68

Found: C, 28.00; H, 1.82; N. 4.39.

EXAMPLE l8 2,2-Bis(chlorodifluoromethyl)-5,5-dimethy14- thiazolidinone s oHa/ iwmom 2-Mercaptoisobutyric acid (3.60 g, 0.03 mol) and 6.6 g (0.033 mol) of 1,3-dichlorotetrafluoroisopropylidenimine were heated on a steam bath under reflux for 16 hours. The product was stirred with 5% sodium bicarbonate and filtered off. Recrystallization from hexane gave 3.90 g (43 percent), mp 69C.

Anal. Calcd for C,H-,C1 F.NOS: C. 28.01; H. 2.35; N, 4. Found: C. 27.85; H. 2.24; N. 4.

EXAMPLE 19 2,2-Bis(pentafluoroethyl)-4-thiazolidinone Anal. Calcd for C-,H,F NOS: C. 24.78; H, 3

0.89; Found: C, 24.56; H. 0

EXAMPLE 20 2-(Dit1uoromethyl)-2-(trifluoromethy1)-4- thiazolidinone product was washed with water and air dried. Recrystallization from hexane gave 514 g (58%), mp 9798C.

Anal. Calcd for C H F NOS: C, 27.15; H, 1.82; N, 6.33

Found: C, 27.82; H, 1.96; N. 6.23.

EXAMPLES 21-24 Prepared according to the procedures given above were:

21: 2,2-Bis(chlorodifluoromethyl )-5-methy1-4- thiazo1idinone, mp 82-83 s In? Toner O NII 22: 2,2-Bis( chlorodifluoromethyl)-3,5-dimethyl-4- thiazolidinone, mp 72-74 S 113T lwmom o NCIIa 23: 2,2-Bis(chlorodifluoromethyl)-3,5-trimethy1-4- thiazolidinone, mp 848 6 and 24: 2-( Difluoromethyl )-2-(trifluoromethyl )-3-methyl- 4-thiazo1idinone, bp 78 (4 mm) CHFz O NCHa EXAMPLE 25 2, 2-Bis(trif1uoromethy1)-5-pheny1-4-thiazolidinone Hexafluoroisopropylidenimine (15 g, 0.091 mol), l ml of dichloromethane, and 15 g (0.089 mol) of a-mercaptophenylacetic acid were sealed in a glass tube and heated at 100 for 5 .hr. After cooling, most l,3-Dichlorotetrafluoroisopropylidenimine (8 g, 0.04 mol), ml of carbon tetrachloride, and 6.72 g (0.04 mol) of a-mercaptophenylacetic acid were heated under reflux on a steam bath for 1 hr. The solvent was of the product was filtered off. More was obtained by 5 evaporated off and the residue was washed with 5 perevaporating the filtrate and washing the residue with 5 cent sodium bicarbonate solution to leave 12.5 g (89 percent sodium bicarbonate solution. The product was percent) of product, mp l59-160 after recrystallirecrystallized from carbon tetrachloride to give 19.2 vg zation from carbon tetrachloride. (68 percent), mp 154l55C.

Anal. Calcd. for CHH1FGNOS: C, 4!.90; H, 2.24; N, 4.44 Anal. Calcd. for C H Cl F NOS: C, 37.93; H, 2.03; N. 4.02

Found: C, 41.55; H, 2.l0; N, 4.33. Found: Q3196; H. 1.93; N, 4.04.

Methylation gave the N-methyl derivative, m.p. 7778C.

EXAMPLE 26 2,2-Bis( chlorodifluoromethyl )-5-phenyl-4- thiazolidinone Methylation gave the N-methyl derivative, m.p. l08lO9C.

The practice of the invention is further shown by Table I. When the mercapto acid of column A is reacted with the imine of column B, the heterocycle of column C is obtained.

TABLE I Column A Column B Column C (CzHQyCCOOH (CF) C=NH s i I 2 (ognmj 01% SH I I (C sH 'QgCCOOH (C F3)2C=NI'I /S I ents): (0 F3): s H

o NH oiHnt lHcoon CFa\ C s /CHF2 SH C=NCH3 a C CHFz I|\ICH3 o F Cl)gC=NH s cmc lnoqou CH2 To F101); s H i o= NIr oiusylcooon (c Fa)gG=NII s (001k) (C F1)? SH HS CI'IQO 00H s (0 F3 io=H T ri):

Hs CHQCOOH (c F C=NC4Hn l S 0; NC4H19 S Substitution on the nitrogen of the heterocycle is fur- \TCFZCDZ ther illustrated in Table ll. When an alkali metal salt of. the heterocycle of column A is reacted with the halide 0 NH of column B, the product of column C 15 obtained.

TABLE 1! Column A Column B Column C s c H I s l (cm a i (Oran O=NH 0 NCsHn' TABLE llContinued Column A Column B Column S IErCll CHOCU. FUQ 7 2 2 5 ll ll were.

Also, reaction of the compounds of column A with ketene produces N-acetyl derivatives. Reaction ofcompounds of columns A or C with molar amounts of I peracetic acid gives the corresponding sulfoxides whereas with excess peracetic acid the sulfones result. The utility of the compounds of the present invention as plasticizers is illustrated by the following example.

EXAMPLE A Similar results were obtained by incorporating the compound of Examples 16 into polyvinyl chloride.

Plant hormone activity is demonstrated by the following example.

EXAMPLE B The compound of Example was applied at 100 ppm on Xanthium leaves. Ethylene production by the leaves as determined by gas chromatography was stimulated 570% over untreated controls. This is indicative of plant regulant activity useful in controlling fruit drop and increasing latex flow in rubber trees. The compound of Example 8 was effective in the prevention of germination of lettuce seeds.

Since obvious modifications and equivalents in the invention will be evident to those skilled in the arts, I propose to be bound solely by the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A compound having the formula t Rs wherein n is O, l or 2.

R and R are hydrogen, aryl, aralkyl, alkenyl, cycloalkyl, alkyl or carboxyalkyl each of up to 8 carbon atoms.

R is hydrogen, alkyl, alkenyl, aryl, aralkyl, hydroxyalkyl, carbalkoxyalky, or haloalkyl each of up to 8 carbon atoms and X is a polymethylene radical of up to 8 carbon atoms, or CH COCH 2. Composition of claim 1 having the formula o NH when R and R are each CF Cl, CF

R is H, CH or CH COOH, and

R is H or CH 3. Composition of claim 2 wherein R and R are each CF Cl.

4. Composition of claim 3 wherein R and R are each H.

5. Composition of claim 1 having the formula 6. Composition of claim 5 where R and R are each CF;,.

7. Composition of claim 5 where R and R are each CF CI.

8. Composition of claim 7 where. R is CH UNITED STATES PATENT oFFIcE CERTIFICATE OF QORRECTIGN Maynard S. Raasch Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 6, Example 10, line 51 change "REcrystallization" to --Recrystallization-.

n QHFQ n Col. 10, Example 2 1, in the formula change to CHF CH 01. 13, Table II delete the first two formulas in columns A, B and C and replace with s s E W (CF Cl) (CH CHBr- W (CFZCDZ NH 0 NCH(CH3)2 s s (cF c1) ClCH CH Br' E W (01 015 0 NH 0 NCH CH Cl V S W(C2F5)2 ClCH COCH I: (C2F5)2 o NCHQCOCH twenty-second D3) 0? July 1975 [SEAL] AIIFSI.

RUTH C MASON C. MARSHALL DANN Am'srmg Officer Commissioner of PGINHS and Trademarks RM PO-105O (10-691 USCOMM-DC 60376-P69 US GOVERNMENY PRINTING OFFICE 9 o 

1. A COMPOUND HAVING THE FORMULA
 2. Composition of claim 1 having the formula
 3. Composition of claim 2 wherein R and R1 are each -CF2Cl.
 4. Composition of claim 3 wherein R3 and R4 are each H.
 5. Composition of claim 1 having the formula
 6. Composition of claim 5 where R and R1 are each -CF3.
 7. Composition of claim 5 where R and R1 are each -CF2Cl.
 8. Composition of claim 7 where R2 is CH3. 